Farm 2 Flashcards
What are the bacterial causes of salivation in ruminants?
Calf diphtheria (necrobacillosis), F. necrophorum, necrotic laryngitis
Actinobacillosis (Wooden tongue)
Actinomycosis (Lumpy jaw)
What are the traumatic causes of salivation in ruminants?
Choke
Drenching gun/bolus injuries/oral burns
Teeth
Vagal nerve damage
Which viral diseases affect the oral cavity of ruminants?
FMD Rabies BVDV BHV-1 (infectious bovine rhinotracheitis) MCF (malignant catarrhal fever, ovine herpes virus-2) Bovine papular stomatitis (BPSV) Orf (parapox virus) Bluetongue
Describe the orf vaccine
Live attenuated vaccine
Scratch vaccine done behind the elbow
VMD product database (do not vaccinate close to lambing, vaccination will not protect lambs via colostrum)
What are the clinical signs of bluetongue in sheep?
Eye and nasal discharges which becomes thick and crusty
Drooling as a result of swelling and/or ulcerations in the mouth
Swelling of the neck and/or the face, especially around the eyes and the muzzle
Severe lameness affected sheep are reluctant to rise
Haemorrhages into or under the skin
Inflammation and pain at the coronary band
A “blue tongue” is rarely a clinical sign of infection
What are the clinical signs of bluetongue in cattl?
Possibly no signs of illness Nasal discharge Swelling of the neck and head, especially around the eyes and muzzle Conjunctivitis Lameness Saliva drooling out of the mouth
What is the causative agent of ‘wooden tongue’?
Actinobacillus lignieresi, gram -ve, facultive anaerobe, oxidase +ve, urease +ve, commensal of the MM
What are the clinical signs of wooden tongue?
Painful, sometimes fever
Stomatitis, glossitis, fibrous tissue, cellulitis evolving in pyogranulomatous infection
Swollen tongue, often protrudes, hard to the touch, submandibular swelling, enlarged Lnn
Salivation and reluctant to eat
Can also affect skin, oesophageal groove, rumen wall etc
May lead to vagal nerve injury
What is the treatment of wooden tongue?
Antibiotics (daily IM >10days)
Sodium iodide (IV, repeate every 10 days) risk it may cause restlessness, tachycardia and staggering
NSAIDs
Prevention: isolate cases and review feeding
What is the causative agent of lumpy jaw?
Actinomyces bovis, gram +ve rods , anaerobic or fa, NON-spore forming, form fungus like branched networks
What are the clinical signs of lumpy jaw?
Swelling Abscesses Fistulous tracts Fibrosis Mucosal damage Painful Suppurative granulation of the mandible and maxilla Hard immobile lesions
How is lumpy jaw treated?
Antibiotics: procaine benzylpenicillin (daily IM >10 days)
Sodium iodide
NSAIDs
The bone deformation will remain after treatment.
What is the causative agent of calf diphtheria (necrotic stomatitis)?
Fusobacterium necrophorum
What is the aeitiology of calf diphtheria (necrotic stomatitis)?
Trauma to buccal mucosa, erupting teeth, contaminated buckets, rough feed
What are the clinical signs of necrotic stomatitis?
Common in calves under 3 mo Necrotic lesions in the pharynx and larynx Swollen cheeks Salivation Foul smelling breath Painful swallowing Cough Inspiratory dyspnea Laryngeal form with stertor more common in older calves 3-18 mo
How is calf diphtheria (necrotic stomatitis) treated?
Isolation
Antibiotics (procaine benzylpenicillin daily IM >5 days)
NSAIDs
TLC
Tracheostomy
Can affect groups so discuss control with the farmer
What are the causes of stomatitis?
Traumatic injuries e.g. drenching gun
Foreign bodies e.g. sticks and root vegetables
Caustic substances on farm
How is stomatitis treated?
Remove decaying food material
Broad spec antibiotics (amoxicillin 5 days
NSAIDs
Discuss management practices
What is the life cycle of fasciola hepatica?
Eggs pass out in faeces
Eggs hatch, miracidians penetrate snail (Galba truncatulata)
Cercariae encyst on submerged/wet vegetation (metacercariae develop)
Ruminants ingest metacercariae
Metacercariae excyst in the duodenum, penetrate wall, enter peritoneum and invade Glissons capsule
Migration to the liver
Flukes reach sexual maturity (in ruminant bile duct)
Minimum period for life cycle completion is 17-19 weeks
What is the pathology of fasciola hepatica?
Parenchymal destruction during migration leading to inflammation and fibrosis
Rarely will damage large blood vessels leading to haemorrhage
Fluke in the bile duct can feed on animals blood leading to anaemia and cholestasis
Anaerobic environment can lead to Blacks disease (infectious necrotic hepatitis)
What are the acute clinical signs of fascoiola hepatica in sheep?
Late autumn / early winter Large numbers of migrating fluke in liver Anaemia – Pale mucus membranes / weak Hypoalbuminaemia Rapidly fatal, animals often found dead
What are the clinical signs of sub-acute fascioloa hepatica in sheep?
Late autumn / early winter Rapid condition loss Anaemia Oedema (Submandibular “Bottle Jaw” or brisket oedema ) Colic
What are the clinical signs of chronic fascioloa hepatica in sheep?
Winter / Early spring Adult fluke sucking blood in bile ducts Poor condition Anaemia Hypoalbuminaemia Submandibular oedema Chronic scour
How do goats present with fasciola hepatica?
Chronic form is most common although sub-acute is seen. Very rare to see sudden death.
What are the clinical signs of acute fascioloa hepatica in cattle?
Rare in cattle
Fibrous nature of liver
Acquired immunity does develop and provides protection (NB whilst antibody can be detected in sheep it appears to be non-protective)
What are the clinical signs of chronic fascioloa hepatica in cattle?
Similar presentation to sheep
Brisket and ventral oedema also seen
What are the clinical signs of subclinical fascioloa hepatica in cattle?
Increasingly recognised
Poor performance (reduced growth rate / reduced yield / loss of condition / predisposes to other disease)
Increased risk of Salmonella dublin?
How is faciola hepatica diagnosed?
Post mortem (fluke in parenchyma and bile duct)
Elevation of liver enzymes AST / GLDH (acute and chronic disease) / gGT (chronic disease bile duct damage)
Faecal egg count (adults must be present so only of use in chronic cases)
Eosinophilia – indicates parasitic infection (useful in subclinical cases)
Blood / bulk milk antibody ELISA (only indicates exposure)
What are the blood biochemistry changes in a faciola hepatica infection?
Aspartate aminotransferase (AST) - Not liver specific, also produced from cardiac and skeletal muscle Gamma glutamyltransferase (γGT) - Good indicator of bile duct damage Glutamate dyhydrogenase (GLDH) - Liver specific, elevated in acute disease Sorbitol dehydrogenase (SDH) - Liver specific, elevated in acute disease Bilirubin - Conjugated increased with bile duct obstruction, unconjugated increased in haemolytic anaemia
What drugs can be used to treat liver fluke?
Triclabendazole Nitroxynil Closantel Clorsulon Oxyclozanide Albendazole
Which drug can be used to treat immature fluke in sheep and cattle?
Triclabendazole
Which drug can be used to treat adult and late immature fluke in cattle?
Nitroxynil
Which drugs can be used to treat adult and late immature fluke in sheep?
Nitroxinil and closantel
Which drugs only treat adult fluke in cattle?
Clorsulon, oxyclozanide and albendazole
Which drugs only treat adult fluke in sheep?
Oxyclozanide and albendazole
How should acute fluke be treated?
Needs activity against early immature fluke (i.e. triclabendazole)
How is fluke treatment delivered?
Drench or subcutaneous injection
Which fluke products are licenced during lactation?
Oxyclozanide and albendazole
How can fluke infection be prevented?
Limit snail habitat
Prevent access to snail habitats (fence of marshy areas)
Application of molluscicides to pasture
Introduction of a predator e.g. geese
Prophylactic treatment (e.g. routine regular treatment of stock, treat when evidence of disease, treatment based on fluke forecast)
What other liver trematodes are there?
Fasciola gigantica
Fasciola magna
Dicrocoelium dendriticum